Flammulina velutipes polysaccharide improves the water-holding capacity in the dorsal muscle of freeze-thawed cultured large yellow croaker (Larimichthys crocea)

To investigate the effect of Flammulina velutipes polysaccharide (FVP) on the water-holding capacity (WHC) in the dorsal muscle of freeze-thawed large yellow croaker, fresh fish were treated with FVP, commercial cryoprotectant (CC), and distilled water before freezing. The water-holding capacity (WHC) and related influencing factors were analyzed. The results showed that FVP was able to effectively improve the WHC by reducing thawing loss and cooking loss, and the effect was similar to that of the CC group. Smaller and rounder ice crystals and less damaged muscle tissue were observed in FVPs. FVP also significantly retarded the protein denaturation revealed by Ca2+-ATPase activity, ultraviolet-visible absorption spectra, and SDS-PAGE of the myofibrillar protein. Furthermore, protein oxidation was inhibited by FVP treatment, as demonstrated by the sulfhydryl group and intrinsic fluorescence intensity. In summary, FVP can effectively improve the WHC by inhibiting the growth of ice crystals, protein denaturation, and potentially protein oxidation.